I'm working on a 3D controller hat for a Raspberry Pi. This is a glimpse of the hardware prototype. You can see the USB and ethernet ports of the Pi on the left side. Features: 4 motor control channels - compatible with A4988 and DRV8825 Stepstick motor drivers - Motor supply voltage up to 45V 3 High power (15A Max) 12v/24v discrete switch channels to drive fans, heaters, extruders, spindles etc. 6 Digital switch inputs for limit switches. ...